Purchased a Sandpiper 365SAQ. After 6 months of use, we started having slide problems. When you hold the button to open, the front, middle and one side goes out. The other rear slide will stop. Even the motor stops. You can let the button off and push it again and it will start moving then stop. This goes on several times. Same thing happens when you go in. Doesn't do it every time. Any ideas? Switch going bad?